Paint-spraying device with rotating brush



April 2, 1963 w. SIMON 3,084,069

PAINT-SPRAYING DEVICE WITH ROTATING BRUSH Filed Dec. 14, 1959 11WIJIIIIAMWIIIIIIIIII INVEN TOR By W ATTORNEY United This inventionrelates to an arrangement by means of which paints, coal-tar colours,and in particular pigments are mechanically applied to the surfaces tobe protected and are spread or rubbed thereonin the same operation.

The principle of the invention also includes the fact that thearrangement is made such that the spreading or rubbing movement iseffected by means of a brush which rotates around an axis of rotation.

According to the invention, :the supply of binder and of the pigment orpigment mixture to the brush is effected by means of a gas subject toexcess pressure, for example air.

The binder and the pigment or pigment mixture are supplied separately,the supply points for the two components being situated inside therotating brush in coaxial relationship to the axis of rotation, whilethe brush $384,069 Patented Apr. 2, 1963 Z rubbing of the paint beingeffected as with an ordinary brush by hand.

In comparison with the prior art, the utilization of meohanical energyfrom the rotary movement in the arrangement according to the inventionoffers a very considerable technical advance, since the operators haveto apply very much less force.

Apart from the mechanical part of the construction, however, and thebetter utilization of the raw materials as a result of elimination ofatomization losses and reduction of the energy expended by the worker,the arrangement according to the invention also affords considerableadvantages inasmuch as the mechanical spreading or rubbing of the paintresults in a very much more intensive bonding to the surface to whichthe paint is applied.

This process is further assisted in the device according to theinvention inasmuch as a very intimate mixing of the liquid binder withthe dry pigment dusts is effected by the bell shape of the applicationdevice. All pigment paints have a very great tendency to settle. Thisdisadvantage is completely eliminated with the invention body forms theseal in relation to the external atmosphere. The brush is to a certainextent so shaped that it forms a bell, at the outer periphery of whichthe brush bristles move in the form of a rim.

The atomization mixing chamber for the two components is situated insidesaid bell, the supply of the binder and of the pigment being effected inco-axial relationship to the axis of rotation by means of a plurality ofinlet nozzles.

Apart from the fact that the coatings of paint are applied and spread orrubbed in the same operation, the technical advance achieved by theinvention lies in the fact that the supply points for the binder and thepigment or pigment mixture are arranged inside the bell, that is to sayin such manner as to be screened off from the external air. In this wayatomization losses are practically eliminated, the respiratory organs ofthe operating staff are protected, and an intimate mixing of thecomponents inside the bell is efiected.

According to the prior art, devices are already known in which theindividual coating components are applied to the support by means of agas subject to excess pressure, for example air. In such a case, the jetof liquid to be atomized surrounds the jet of powder to be atomized.There is no sealing off from the external atmosphere however. It is alsoknown to combine the spraying device and the spreading brush in oneapparatus. In this case, however, in comparison with the invention thesupply of spreading liquid is effected outside the brush. A commonfeature of these two earlier constructions is that there areconsiderable atomization losses and the respiratory organs of theoperators are not protected from adverse effects. Similar disadvantagesare found in another case in which two spray-guns coupled together areused, one for the binder, the other for the pigment. In this case thereis no spreading means such as the brush, and the pigment is introducedby the excess pressure into the binder only on the surface to beprotected. This application requires very accurate manipulation since assoon as the binder dries and forms a skin on the said surface theintroduction of the pigment can no longer be effected satisfactorily.

In another case the supply of coating substance is effected through theshaft of a brush. This brush, however, performs no rotar-y movement, thespreading and of very great advantage.

and the concentration or quantitative regulation of the pigment may beefiected up to 95%.

Binders and pigments of the most diverse kinds may be used by theprocess of the invention. The use of the invention is not limited tocertain material properties of the binder and pigments. Hereinafter aregiven a number of examples for the composition of binders and pigmerits:

Using metals of the kind from which metallic powders can be made it ispossible, by means of suitable binders, to produce a met-allization onany desired surfaces. In this connection use may be made, for example ofzinc, lead, copper, cadmium, nickel, or brass in powder form.

Instead of metallic powders it is also possible to use non-metallicpowders, 'for example rubber, basalt, glass,

porcelain, mica, asbestos and similar substances. According to thedifferent requirements of the protective coatings, combinations ofdifferent coatings which follow one another and are adapted to oneanother are also By way of example, on a steel surface, zinc may beapplied in the first instance as cathode protection, and then a coatingof glass powder be applied thereto. This combination is particularlyimportant for the protection of steel structures against industrialwaste gases. For protection against chemical attacks, a lead priming canbe used first, and over that a coating of basalt or glass, a high-gradesynthetic resin being used as binder.

Coal-tar colours can be used in similar manner with zinc or lead powderas priming and coatings of silicon carbide thereover as protectionagainst chemical attacks.

The composition of the individual coatings and the combination of aplurality of coatings depend on the particular purpose required, and ithas been found particularly advantageous that concentration of thepigments up to relative to the binder is possible. Even with such a highproportion of pigment the films are completely unstressed on thesurface, are flexible and do not crack when the coating is subjected toalternating stresses.

In the accompanying drawings, FIG. 1 shows the actual spreading meansand FIG. 2 the complete spreading device.

In FIG. 1, reference 1 denotes the housing, which contains the drive forthe brush. Reference 2 is the housing for the motor 3, and the gear 4for the power transmission from the motor to the brush. Reference 5denotes the bearings for the movable parts. The forms of powertransmission and bearings are intended only as examples, and may beembodied in any other manner.

The hollow shaft by means of which the brush is driven is denoted byreference 6. The supply means 7 and 8 for the binder and pigment aretaken through the hollow shaft. The annular brush is denoted byreference 9, and 10 indicates a suspension eye, by means of which thedevice can be suspended as required when in use, so that the operatorshands are freed.

The mode of operation is therefore such that pigment and binder passinto the interior of the annular brush through the supply means 7 and 8by means of a gas under pressure, for example air, and are spread afterbeing mixed by the brush. The motor housing 2 simultaneously serves ashandle for operation.

FIG. 2 shows the complete spraying device. The annular brush 9 is joinedfast by its housing to the motor housing 2. Reference 11 is the supplycable for the electric current, which is switched on and 01f by means ofthe switch 12. The supply means 7 and 8 for the pigment and binder areconnected to the housing 1 by means of hose clips 13, 14. Valves 15 and.16 are provided, one each in the supply means 7 and in :the supplymeans 8, for regulation purposes for the supply and batching of thepigment and binder. Reference 17 denotes a belt, by means of which theoperator is relieved of the weight of the supply lines.

The pigment is disposed in the powder mixing container 18, which isequipped with a pressure gauge 19 and a filler screw 20. The binder isdisposed in the pressure container 21, which is likewise equipped with apressure gauge 19.

The binder and pigment are fed by means of a gas under pressure, forexample air. This gas is fed to the system at 22 and on the one hand, byway of the reduction valves 23 and 24, is connected to the powder mixingcontainer 18 and the pressure container 21 for the binder and, on theother hand, by way of the pressure line 25 and the reduction valve 16,is connected to the pigment supply.

The apparatus is fed with pressure gas by means of a compressor of any:type of construction.

The operator who, as already stated, is relieved of the weight of thesupply lines by means of the belt 17, can conveniently carry out thecoating operations, since all the supply means consist of elasticmaterialrubber or synthetic plastic materials.

I claim:

1. An applying device adapted to apply a paint comprising a pigment anda binder, said device comprising: an annular rotatable brush, said brushhaving bristles and a head; a housing connected to said brush head,means carried on said housing and operatively connected to rotate saidbrush; plural separate supply means adapted to contain said pigment andsaid binder respectively, separate supply conduits operatively connectedto said supply means and to said brush, said conduits terminating withinthe bristles of said brush, for separately feeding said pigment and saidbinder from said supply means into the inner portion of said rotatingbrush, whereby desired quantities of said pigment and said binder may bemixed within the brush bristles and applied to a base by contact withsaid bristles and separate operating controls for said supply conduits.

2. A paint applying device according to claim 1 wherein the means forrotating said brush and said operating controls are disposed in thevicinity of the brush within reach of the operator of said device.

3. A paint applying device according to claim 1 wherein said bindersupply means is pressurizable for forcing the binder to said brush in asubstantially air-free state.

4. A paint applying device according to claim 3, wherein said pigmentsupply means is pressurizable for forcing said pigment to said brush andmeans for feeding .additional air under pressure to the supply conduitfor said pigment.

5. .A method of applying paint wherein separate streams of pigment andbinder are separately supplied to the center of a movable rotatingannular brush, "being thereby mixed within the brush, and wherein thepigment and binder are simultaneously applied to a base by contactingsame with the rotating brush.

6. The method of claim 5 wherein the pigment is supplied to said brushas a mixture of pigment and air, and wherein the binder is supplied tosaid brush in a substant'ially air-free state.

7. A paint applying device according to claim 1, wherein said pigmentsupply means is pressurizable for forcing said pigment to said brush andmeans for feeding additional air under pressure to the supply conduitfor said pigment.

References Cited in the file of this patent UNITED STATES PATENTS189,828 Woodcock Apr. 17, 1877 626,750 Carter June 13, 1899 1,034,988Dykes et al Aug. 6, 1912 1,287,121 Skau Dec. 10, 1918 2,380,827 DownsJune 31, 1945 2,757,406 Decker Aug. 7, 1956 2,806,236 Di Stefano Sept.17, 1957

1. AN APPLYING DEVICE ADAPTED TO APPLY A PAINT COMPRISING A PIGMENT ANDA BINDER, SAID DEVICE COMPRISING: AN ANNULAR ROTATABLE BRUSH, SAID BRUSHHAVING BRISTLES AND A HEAD; A HOUSING CONNECTED TO SAID BRUSH HEAD,MEANS CARRIED ON SAID HOUSING AND OPERATIVELY CONNECTED TO ROTATE SAIDBRUSH; PLURAL SEPARATE SUPPLY MEANS ADAPTED TO CONTAIN SAID PIGMENT ANDSAID BINDER RESPECTIVELY SEPARATE SUPPLY CONDUITS OPERATIVELY CONNECTEDTO SAID SUPPLY MEANS AND TO SAID BRUSH, FOR SEPARATELY FEEDING WITHINTHE BRISTLES OF SAID BRUSH, FOR SEPARATELL FEEDING SAID PIGMENT AND SAIDBINDER FROM SAID SUPPLY MEANS INTO THE INNER PORTION OF SAID ROTATINGBRUSH, WHEREBY DESIRED QUANTITIES OF SAID PIGMENT AND SAID BINDER MAY BEMIXED WITHIN THE BRUSH BRISTLES AND APPLIED TO A BASE BY CONTACT WITHSAID BRISTLES AND SEPARATE OPERATING CONTROLS FOR SAID SUPPLY CONDUITS.